Copyright 2021 - TSR - Tratamiento de la Señal y Radiocomunicaciones

Susana LÓPEZ

PhD. Thesis Title

A study for optimizing the field strength prediction of the digital services for ground-wave propagation in the MW band



Emerging digital radio systems developed for their use in the LW, MW and SW frequencies take advantage of the excellent propagation conditions at these frequencies. Besides, they provide a high audio quality and they incorporate data services. The IBOC/HD Radio and DRM systems were accepted by the international committees and agencies and have been adopted as a standard by many countries. The numerous experimental networks to verify the operation of these systems, the increasing trading emissions and the requests promoted by the ITU for further exploration of the propagation below 30 MHz demonstrate the revitalization of these bands.

These systems, due to their digital nature, require a very high degree of coverage, and thus, a high accuracy in planning tools. The reason is that a signal level below the threshold necessary for good reception implies a poor quality in the analogue systems, but a lost of the service in the digital ones. To achieve the required accuracy it is necessary a deep analysis of the ground-wave propagation channel and the spatial variability of the signal under several reception conditions.

This thesis provides a method for predicting field strength level for ground-wave propagation in the MW band for digital services planning.

Firstly, this thesis makes contributions related to the influence of several factors in the field strength variability in the MW band. Then, a method for field strength prediction, which provides more accurate results than the existing methods for the analogue services, is proposed. The proposed method is composed of a point-to-point model and a point-to-area model.

The studies described in this document have been performed at the University of the Basque Country (UPV/EHU). This institution is member of the international DRM Consortium, which is responsible for promoting the DRM standard. The TSR research group (Signal Processing and Radiocommunications research group) plays a very active role in the System Evaluation Group of the Technical Committee (SE/TC) of the DRM consortium for the validation of the system through field tests.